Such pump systems for example are to be found in well fields, in which several wells each with at least one pump delivering water in parallel out of the wells are present. The pumps can be taken into operation in different numbers and with a different speed, depending on the required quantity of water.
Moreover, pump systems are known, with which several pumps are connected in series for increasing the pressure. Thereby, the pumps can be operated in a different number or different power depending on the head of the pressure difference to be produced.
If in such pump systems, different types or different sizes of pumps, or pumps with different hydraulic connection conditions are operated together, it is difficult to optimize the operation of the individual pumps such that the desired hydraulic load, which is to say a desired different pressure or flow, can be achieved with minimal energy consumption.